In drilling a wellbore, drilling fluid is used to facilitate the drilling process and to maintain a hydrostatic pressure in the wellbore greater than the pressure in the formations surrounding the wellbore. The drilling fluid penetrates into or invades the formations depending upon the types of the formation and drilling fluid used. The formation testing tools retrieve formation fluids from the desired formations or zones of interest, test the retrieved fluids to ensure that the retrieved fluid is substantially free of filtrates. The testing tools further collect fluids, for example, in one or more chambers associated with the tool. The collected fluids are brought to the surface and analyzed to determine properties of such fluids and to determine the conditions of the zones or formations from where such fluids have been collected. In order to properly analyze the samples, it is important that only uncontaminated fluids are collected in the same condition in which they exist in the formation. For example, the fluid is maintained in a single phase, which is done by maintaining the pressure of the fluid constantly above the bubble point.
Conventional formation tester tools may need to manipulate the sample fluid to make fluid property measurements such as the bubble point by periodically measuring the static bubble point. This requires the pumping operation to cease during the fluid measurement, allowing contamination to encroach into the sample zone, and further slowing the overall pumping process.
Accordingly, what is needed is a testing operation or pumping operation that does not require the pumping operation to cease while testing the fluid.